1. Field
A scroll compressor is disclosed herein.
2. Background
In general, scroll compressors are widely used for refrigerant compression in air-conditioners, to obtain a relatively higher compression ratio in comparison to other types of compressors, and acquire a stable torque resulting from smooth strokes of suction, compression, and discharge of the refrigerant. A behavior of the scroll compressor is dependent on shapes of a fixed wrap and an orbiting wrap. The fixed wrap and the orbiting wrap may have a random shape, but typically they have a shape of an involute curve, which is easy to manufacture. An involute curve refers to a curve corresponding to a track drawn by an end of a thread when unwinding the thread wound around a basic circle with a predetermined radius. When such an involute curve is used, the wrap has a uniform thickness, and a rate of volume change of the compression chamber is constantly maintained. Hence, a number of turns of the wrap should be increased to obtain a sufficient compression ratio, which may, however, cause the compressor to be increased in size corresponding to the increased number of turns of the wrap.
The scroll compressor may be provided with a rotation-preventing member, such as an Oldham ring, provided between the orbiting scroll and a frame that supports the orbiting scroll or a fixed scroll, so as to induce an orbiting motion by preventing rotation of the orbiting scroll. However, when the Oldham ring is provided in the scroll compressor, a gap is formed between a key and a key groove, which are located at or on the Oldham ring and the orbiting scroll, respectively. The gap may cause the orbiting scroll to be temporarily rotated or inversely rotated during operation. Due to the rotation or inverse rotation of the orbiting scroll, an interference or gap may be formed between an orbiting wrap and a fixed wrap according to a crank angle in each of a compression chamber (hereinafter, referred to as “a first compression chamber”) formed outside of the orbiting wrap, and a compression chamber (hereinafter, referred to as a “second compression chamber”) formed inside of the orbiting wrap. This results from the fact that an orbiting radius of the orbiting wrap changes without remaining still at a moment of the rotation or the inverse rotation of the orbiting scroll. When the fixed wrap and the orbiting wrap have an involute or algebraic spiral shape, in which a wrap curve of the fixed wrap and the orbiting wrap has a uniform shape along a turning direction of the wrap, the interference or gap is minorly generated. However, in a scroll compressor in which the wrap curve of the fixed wrap and the orbiting wrap is irregular in the turning direction of the wrap, a great interference or gap may be generated. In this manner, if such interference or gap is generated at a specific portion between the orbiting wrap of the orbiting scroll and the fixed wrap of the fixed scroll, abrasion due to interference between the wraps or compression loss due to the gap between the wraps may be caused.